<strong>STMicroelectronics Enables Cloud-Based Vertical Location Service for Barometric Height Sensing in Wi-Fi 6E7 Implementations</strong>

The STMicroelectronics LPS22DF pressure sensor officially received the NextNav certification, which ensures performance and reliability for geolocation and other types of applications. NextNav Certified is a program established by NextNav to ensure that devices, applications, and solutions meet specific requirements to utilize their technology effectively, such as E911 devices. This certification ensures that products and services integrate seamlessly with NextNav’s vertical positioning location services and have undergone rigorous testing to meet performance benchmarks. A NextNav certification thus demonstrates that a product like the STMicroelectronics LPS22DF is reliable, accurate, and compatible with NextNav’s technology.

Beyond devices and applications calling emergency services, new systems are now seeking NextNav certifications. For instance, WiFi 6E/7 devices use pressure sensors to enable a maximum access point (AP) power mode and coverage with precise vertical positioning. A NextNav certificate often plays a role in helping a company decide whether to qualify one device over another for a specific application. New network devices also use such Microelectromechanical systems (MEMS) to report their location. Put simply, accurate and reliable pressure sensors like the ST LPS22DF are opening the door to new use cases in consumers and industrial markets, to only name a few.

Wi-Fi is an example of this. In the space of just two decades, Wi-Fi has come from nowhere to be everywhere, with the latest data suggesting there are more than 30 billion connected devices worldwide. With such astonishing scale and continued predicted growth on a similar trajectory, comes a demand for better and more capacity, reliable connectivity, and support for ever increasing speeds. Wi-Fi 6E/7 can address this, enabling devices to operate in the unlicensed 6 GHz spectrum where it makes use of super-wide channels that support greater capacity, lower latency, and increased throughput.

However, there is a challenge, and that is managing the interference between Wi-Fi access points (APs) and other systems already operating in the same 6 GHz spectrum. These include point-to-point microwave and earth-to-satellite communications requiring precise location data encompassing vertical position in addition to horizontal X and Y axis positioning. In fact, for AP installers and system operators making use of Wi-Fi 6E/7, an automated solution for vertical location recording is a pre-requisite to satisfy FCC regulation FCC-20-51, which necessitates providers to report height to the Automatic Frequency Controller (AFCs) that control them. To achieve this, an accurate sensor technology able to provide height-above-ground data is needed. This must then be paired with a reliable cloud-based service to convert the raw sensor measurements into meaningful vertical location data.

An effective way to do this is by employing a barometric pressure-based solution for each AP. The choice of sensor is particularly critical as many are susceptible to ‘drift’ away from an accurate measurement over time. Drift is a natural phenomenon, and its contributing factors include pressure changes, frequency and amplitude shifts, temperature and humidity extremes, material responses and other environmental variations. For installers to comply with FCC-20-51, it is important to select a resilient low-drift sensor that can consistently report the observed pressure at the AP within +/-10-15Pa of reality – ideally for the whole life of the device.

Converting the measurement from the barometric pressure sensor in the AP into an accurate height above ground vertical location value with 95% confidence and regardless of weather conditions requires the use of real-time, accurate, reference pressure data that factors in environmental conditions such as weather changes during the day as well as air pressure variances measured within a very localized area. Achieving this is possible with cloud-based services that support device data, surveyed localized weather station measurements and suitable software algorithms. Architectures for reporting can be as simple as the AP directly reporting to the AFC. or, in the case of multiple APs, an enterprise service manager or proxy server.

Sensors such as the STMicroelectronics LPS22DF which are well-suited to generating pressure-based altitude data in Wi-Fi AP deployments, combined with NextNav’s Pinnacle cloud-based vertical location service offer a reliable and robust solution for providing access point installers and system operators on-demand height generation using real-time pressure data.

To find out more about how this solution can provide accurate elevation data in the ‘height above ground’ format that the FCC regulations demand, contact us here.